Google’s disproportionate usage of long-term independent contractors has recently come under fire and now faces pressure from Congress.

A group of 10 Democratic Senators has come forward to urge the tech giant to reclassify any contractors that work for longer than six months as full-time employees. In a letter addressed to CEO Sundar Pichai, the Senators accused Google of abusing the distinctions between contractors and employees and pushed for immediate action, as reported by CNBC.

“Temporary workers and independent contractors are by definition intended for short-term and non-core work, and we urge Google to end any abuse of these worker classifications and treat all Google workers equally,” the letter urged. “The differences between the categories of workers appears to be in name only. In at least some cases, your company determines where these individuals work, the hours they work, the tasks they perform, and whether or not they should continue to work on Google contracts.”

The letter is signed by Democrat Sens. Sherrod Brown, Patty Murray, Benjamin Cardin, Brian Schatz, Elizabeth Warren, Kamala Harris, Edward Markey, Richard Blumenthal, Richard Durbin and independent Bernie Sanders. Warren, Harris and Sanders are currently running for president on the 2020 Democrat ballot.

Google’s classification practices came under fire after a New York Times article in May revealed that the company employs 121,000 contract workers and only 102,000 full-time employees, despite some contractors seemingly performing the same work as full-time employees. This allowed the company to pay less for the same work, as contractors earned a median salary of $90,000, as opposed to full-time workers who made $128,000.

The letter also called for benefit parity between contractors and full-time employees, and for greater transparency in letting contractors know when they can expect to transition to full-time status.

Google disputes these issues.

“We are proud to create economic opportunities for both the people we employ directly and our extended workforce of vendors, temporary staff and independent contractors, and believe that our practices in this regard accord with the highest industry standards,” said Eileen Naughton, VP of people operations. “Respectfully, we strongly disagree with any suggestion that Google misuses independent contractors or temporary workers.”

Elizabeth Warren
In this photo, Elizabeth Warren (D-MA) addresses a rally against Trump Administration budget cuts to education funding outside the U.S. Capitol in Washington, D.C., July 19, 2017. Getty Images/ Chip Somodevilla